This invention relates to air inlets for a central vacuum system within a building.
Central vacuum systems are quite common now in homes and other buildings requiring regular vacuum cleaning. Because it is not necessary to move around a rather heavy vacuum cleaning unit, they are rather convenient to use. It is simply necessary to hook up a long cleaning hose to an inlet structure mounted in a convenient wall. This inlet structure is connected by a hidden pipe system to the central vacuum source. Another advantage of such a system is that the system can provide a fairly high level of vacuum because a large vacuum creating fan can be employed at the fixed vacuum source.
In the commonly used central vacuum system, there is a standard wall mounted opening to which one end of the hose can be readily attached. Often there is a flap that can be used to close the opening and thereby prevent air entry when the air inlet is not in use. Also, the end of the hose attached to the opening may actuate a switch by joining two electrical terminals and thereby closing an electrical circuit that is connected to the central vacuum source.
One difficulty with this known, commonly used central vacuum system is that in order to clean up even a small spill or mess, it is necessary to take out and hook up a rather large, long hose and this can be inconvenient. Areas such as kitchens and dining rooms often require frequent cleaning because of the food preparation and eating that is carried on in these rooms. Also, because of the activities in these rooms, the floors are often not carpeted but have a hard, smooth surface. In such areas, rather than taking the trouble to hook up the long hose of the central vacuum system, a person may choose to use instead a dust pan and a broom or brush but these also can be inconvenient and time consuming to use.
Recent U.S. Pat. No. 5,279,016 dated Jan. 18, 1994 and issued to T. J. Klassen, describes a suction inlet for a central vacuum system that can be used without the need for hooking up a long hose to the inlet. In one version of this device a rectangular, box-like housing is mounted in or behind a baseboard or kick plate and it has an elongate, horizontally extending slot in its front, which slot is covered when the inlet device is not in use. An elongate, pivoting lever, one end of which projects from the front of the housing is connected by means of a vertical pin to a flat, rubber plug which extends over an aperture in a bottom plate. This aperture is connected to a hose or pipe that leads to the central vacuum source. By pressing with one's foot on the end of the lever, one is able to open the aperture and at the same time close an electrical circuit and thereby cause the central vacuum source to operate.
There are several difficulties that can arise with the use of the inlet structure of the aforementioned U.S. patent. The first is that in order for the inlet structure to operate in a cleaning situation, not only must one press on the actuating lever but one must continue to hold one's foot on this lever in order to keep the aperture open and the central vacuum source on. In addition, because of the nature of the housing and its box-like structure, there are likely to be "dead" zones in the housing where dirt and debris will be trapped and will not be drawn into the vacuum hose or pipe. It could be quite difficult to clean the interior of this known housing using other cleaning methods. The vertical pin and the rubber plug will create an obstruction in the chamber. Dirt and debris will get caught on these members causing blockages especially long debris such as string, hair and cloth, etc. If blockage occurs, the plug will not create a seal and power will be reduced substantially to all outlets in the system. This blockage could occur without the user knowing.
Another difficulty arises from the fact that this known system requires a hole to be cut in the floor of the building to permit the vacuum cleaning pipe to be connected from below. It may, in fact, be much more convenient for the builder or home owner to be able to connect the inlet structure at its top or side wall to the pipe or duct of the system. Also location of the outlet at the bottom of the chamber as taught in this U.S. patent specification will allow gravity to draw debris into the piping system that is too heavy for the vacuum system to carry. This will cause blockage in the piping resulting in expensive repair work.
U.S. Pat. No. 3,027,588 issued Apr. 3, 1962 to H. Bierstock describes a rather complex apparatus for picking up floor sweepings at a baseboard using a vacuum source or vacuum cleaner. This known apparatus includes an elongated nozzle having a lower lip portion that can be extended through a baseboard aperture adjacent the floor area. The nozzle is mounted at one end of a tube on which a piston is fixed. This piston is reciprocably mounted in a housing chamber. A controllable valve mechanism selectively leads the vacuum from the hose to the tube and nozzle or to either side of the piston to advance or retract the tube and the nozzle device. This known apparatus would be quite expensive to build and instal and would not appear to be practical for most home applications.
It is an object of the present invention to provide an improved inlet structure for a central vacuum system which can be used without the need for attaching a long hose and which is relatively inexpensive to manufacture and install and is easy to use.
It is a further object of the present invention to provide an inlet structure for a central vacuum system wherein the housing forming the vacuum inlet chamber is shaped in such a manner that dirt and debris will not easily become trapped somewhere in the chamber and will be readily passed through the chamber into the attached hose or pipe of the central vacuum system.
It is an additional object of the invention to provide an improved inlet structure for a central vacuum system which is relatively easy to install in a wall of a building or house and which can be readily connected to a pipe leading to a central vacuum source.